The invention relates to dispensing apparatus for dispensing materials, such as liquids and powders, into containers in a selective manner. The dispensing apparatus is particularly designed for cooperation with designated containers which have at least one predetermined shape component which cooperates with the dispensing apparatus to control a dispensing operation.
In many organisations, for example in industry, in large kitchens and in hotels where many rooms must be cleaned regularly, small containers, such as easily portable bottles, are frequently refilled with cleaning and sanitising liquids from bulk containers held at a filling station. The filling of each container may involve dilution of the liquid contained in the bulk container.
At such a filling station, there may be two or more different liquids stored in bulk and available for dispensing. Different dilutions of one liquid may be required for different purposes. The containers being filled may be labelled or coloured, in order to indicate the liquid which they should contain. There are obvious risks of error here, that the wrong liquid may be filled into a container, particularly when many people frequently visit the filling station. Simple colour coding systems are employed, but do not remove the possibility of human error.
Attempts have been made to overcome this problem by electronic automated filling systems, but these tend to be very complex, involving for example reading of bar code labels. Such systems are expensive and require expert set-up and maintenance.
A simple mechanical control system aiming to achieve filling of a container only with the correct liquid is described in EP-A-675073, where the container has a predetermined profile which corresponds with a specific liquid to be dispensed. Unless slots on the container match projecting pins on a cradle of the dispenser which receives the container horizontally, the container cannot reach the filling position at which it actuates a filling switch on lifting of the cradle. A similar partially mechanical arrangement is shown in EP-A-726874 where movable pins on the cradle, which are selectively depressed by the profiled container as it is pushed onto the cradle, actuate microswitches which through electrical control circuitry cause the desired one among several liquids to be dispensed, when the bottle is lifted in the cradle.
The present invention seeks to provide a simple and low-cost dispensing apparatus which achieves automatic dispensing of material, such as liquid or liquids, selectively into specific containers, without electronic data handling and even possibly without any electrical control devices.
According to the invention there is provided dispensing apparatus for dispensing material into a container having at least one predetermined shape component selected for cooperation with the dispensing apparatus to control a dispensing operation, the dispensing apparatus having:
(i) a vertically movable support for the container having a first, lower position at which the container is brought into a mounted position on the support and a second, higher position,
(ii) actuating means arranged for mechanical engagement with the container during lifting of said container when mounted on the support by movement of the support to said second position thereof, the actuating means being adapted to cooperate with the predetermined shape component or components of the container to determine, in dependence on the shape of the shape component or components, at least one of
(a) the material or materials to be dispensed into the container among a plurality of materials available for dispensing
(b) the quantity of a material to be dispensed into the container.
Preferably the dispensing apparatus, where used for dispensing liquid, comprises at least one pump having a pumping member movable to pump liquid into the container mounted on the support, the actuating means having an actuating member which is mechanically linked to said pumping member to cause pumping movement thereof and which is arranged to be engaged and moved by one said shape component of the container as the container is lifted by the support, so that the shape of the shape component determines the travel of the actuating member thereby determining the amount of liquid pumped by the pumping member. There may be a plurality of pumps having respective pumping members movable to pump liquid into the container mounted on the support, the actuating means having a plurality of actuating members mechanically linked to the respective pumping members to cause pumping movement thereof and arranged to be selectively engaged and moved by the shape component or components of the container as the container is lifted by the support, so that the shape component or components determines which of said pumping members is moved.
To allow accurate dispensing of different volumes of liquid, using appropriately dimensioned pumps, preferably the amount of liquid dispensed, per unit length of travel of the container when mounted on the support, is larger in a first one of the pumps than in a second one of the pumps. Thus a pump of large capacity can be selected for larger volumes to be dispensed and a pump of smaller capacity for smaller volumes.
In a convenient and simple arrangement, the or each pump comprises a cylinder and piston in the cylinder, the cylinder being the movable pumping member, wherein the upward movement of the support causes upward movement of the cylinder relative to the piston to effect pumping. To improve venting of any air in the pumping system, preferably an outlet path is provided from the cylinder which path extends upwardly from the cylinder to a venting location without a downward path portion, whereby air present in the cylinder tends to be vented therefrom on operation of the pump.
The apparatus preferably includes at least one shut off valve openable to permit dispensing of liquid into the container, and a contact member arranged to be engaged and moved by the container when the container is correctly mounted on the support for a dispensing operation, the contact member being linked to said shut-off valve so as to maintain said shut-off valve closed unless the container is correctly mounted on the support. In this arrangement, said contact member may be arranged to move with said support and to move said actuating member or members on lifting of said support when no container is mounted on the support for dispensing of liquid, thereby moving said pumping member or members so as to cause pumping of the liquid to a storage container or containers therefor.
The dispensing apparatus of the invention can be mechanically simple and can avoid the use of electrical switches and electrical control circuitry. Indeed, the need for electrical power can be eliminated. The natural and necessary action of lifting the container, typically in relation to a dispensing nozzle, is combined with the action of selection by the container shape of the nature and/or quantity of liquid or other material dispensed, and preferably in itself effects the pumping of the liquid.